Sound transmission in building structures of concrete

Direct sound transmission through walls and structure-borne sound transmission via junctions between slabs and walls are discussed for dwelling houses with bearing concrete constructions. The theoretical calculations of the direct transmission are based upon Cremer's paper of 1942 -xb[1]. By introducing the total losses and an area factor, Cremer's theoretical results can be used with good approximation to calculate the reduction index for finite constructions. This is illustrated by comparisons with experimental data. Comparisons are also made between measurements and calculations of structure-borne sound transmission via junctions between walls and slabs. For many cases this agreement is satisfactory. One example is given in the paper. In the theoretical calculations, diffuse incidence of the bending waves at the junction is assumed. The results also show that when considering bending wave transmission, it is necessary to take longitudinal and transverse wave fields into account. A more detailed discussion of the structure-borne sound transmission problem is found in another paper -xb[2].